Treesearch

This document presents forest ecosystem carbon yield tables, representing stand-level merchantable volume and carbon stocks as a function of stand age, for 53 forest types within 11 regions of the United States. These tables are an update from previous forest carbon stock estimates and were developed in support of U.S. Department of Agriculture greenhouse gas estimation guidelines for agriculture and forestry. The uncertainty of results obtained with these methods may be high relative to other techniques that use site- or project-specific data. The estimates presented here nonetheless...

A critical load (CL) is a science-based threshold that identifies the amount of pollutant deposition below which no significant ecological harm to an ecosystem component is expected. This report provides baseline critical load (CL) analyses for nitrogen (N) and sulfur (S) as required under the 2012 Planning Rule for forest plan assessments. The data also can be used to inform land management decisions where the effects of N and S deposition are relevant, including the evaluation of large projects through the National Environmental Policy Act, Prevention of Significant Deterioration (PSD)...

i-Tree is a suite of computer software tools developed through a collaborative public-private partnership. These tools are designed to assess and value the urban forest resource, understand forest risk, and develop sustainable forest management plans to improve environmental quality and human health. This report provides details about the underlying methods and calculations of these tools, as well their potential limitations. Also discussed are the history of i-Tree, its future goals, and opportunities to facilitate new science and international collaboration. This report is a revision to...

An assessment of the vegetation structure, function, and value of Baltimore's urban forest was conducted during 1999, 2004, 2009, and 2014. Data from 193 field plots located throughout Baltimore were analyzed using the i-Tree Eco model developed by the USDA Forest Service, Northern Research Station. In 2014, the most common tree species across public and private lands were American beech, American elm, and green ash (encompassing all woody plants greater than 1 inch in diameter at breast height). The number of trees in Baltimore's urban forest declined from an estimated 2,631,000 trees in...

Purpose of Review. Climate change is modifying the dynamics of forests and threatens the supply of ecosystem services from managed forests. In response, managers are developing climate-adapted strategies, mostly focusing on changes in abiotic conditions. Ungulate populations, however, also impact forest integrity and productivity, and the effects of ungulate browsing likely interact with the effects of climate change. This raises the issue of whether climate-adapted strategies will be compatible with abundant ungulate populations. Here, we endeavour to (1) review if/how climate-adapted...

We sampled 130 individuals (2 to 25 per taxon) of Pinus subsections Ponderosae and Sabinianae. Nucleotide sequences were obtained by targeting 703 low copy nuclear genes. From the unenriched portion of the short reads, we assembled nearly complete plastome nucleotide sequences. We used 600 nuclear genes and the plastome sequences to create phylogenies and species trees that we compared to evaluate cytonuclear concordance and reticulation. We found that Pinus jeffreyi belongs with Pinus subsect. Sabinianae based on morphological synapomorphies as well as strong molecular phylogenetic...

While emphasis with entomopathogens has often been on inundative releases, we describe here historic widespread inoculative releases of a fungal entomopathogen. Several U.S. states and municipalities conducted inoculative releases of the gypsy moth, Lymantria dispar (L.) (Lepidoptera: Erebidae), pathogen Entomophaga maimaiga Humber, Shimazu et Soper (Entomophthorales: Entomophthoraceae) after 1993, as gypsy moth populations spread into the Midwest and North Carolina. This Japanese pathogen first caused epizootics in northeastern North America in 1989 and methods for its inoculative release...

Forests provide key ecosystem services globally, with economic values ranging from $125 to $145 trillion per year (Costanza et al., 2014). Forests are important not only for carbon sequestration goals and global biodiversity (Bonello et al., 2020a; Di Sacco et al., 2021; Palmer, 2021), but also for the economic (e.g., timber), environmental (e.g., water purification), and social (e.g., recreational activities) benefits (Trumbore et al., 2015) they provide (Bastin et al., 2019, 2020). Increasingly, forests are viewed as directly important to human health (Donovan et al., 2013); indeed,...

This report summarizes the potential impacts of N and S deposition on 94 of the most common tree species across the contiguous United States, compiling information from several peer-reviewed Federal and non-Federal sources. We provide information on how the rates of growth and survival for each species respond to N and S deposition, and the ecological roles and ecosystem services provided by these species. This report is part of a three-volume series covering trees (this Volume 1), lichens (Volume 2), and herbaceous understory species (Volume 3). In this volume, we include five categories...

The impact of fuelwood harvesting on forest structure and composition is not clear, especially on the understudied and scarce Arasbaran forests in Iran. This research compared woody species density, species diversity, forest composition, and regeneration status in areas of continuous and ceased fuelwood harvesting in Arasbaran forests. We expected fuelwood harvesting to decrease stem density, species diversity, tree size (diameter at the breast height (DBH) and height), and shift composition away from preferred fuelwood species. We measured woody species size and frequency and identified...